Add and subtract counter



D Oct. 21, 1958 w. w. HOFFMANN ETAL 2,851,101.

ADD AND SUBTRACT COUNTER Filed De c. 2, 1955 D 2 Sheets-Sheet 2 MIA/70.38: Walter 719. Jfqfmam 2,857,101 ADD ANDSUBTRACT coUNrER Walter W. Holfmann, Waukesha, and Clarence W.

Bra-atz, Milwaukee, Wis., assignors to Durant Manufacturing (10., Milwaukee, Wis., a corporation of Wiscousin Application December 2, 1955, Serial No. 550,644,

2 Claims. (Cl. -235--92) This invention relates to improvements in electric counters of the type which will add and subtract electrical impulses from separate sources.

In U. S. Patent No. 2,673,685, issued March 30, 1954, there is described and claimed an intermittent counter drive by which electrical impulses from a single source are added. The invention herein described utilizes to a large extent the same mechanism for transferring the electrical impulses to the rotary number wheels of the counter and reference should be madeto such patent for the details of construction not particularly described herein.

An object of this invention is to provide a counter in which impulses from one source are added and impulses from another source are subtracted to provide a continuously visible difference.

Another object of this invention is to provide an add and subtract counter which is relatively inexpensive to manufacture, simple in construction, efficient in operation, and capable of counting at high speeds.

These objects are obtained by utilizing two solenoids each operating separate ratchet wheels through oscillatory drive arm assemblies. The drive arm assemblies include operating pawls which-are automatically moved to nonactuating position when a solenoid and its drive arm assembly is in non-energized neutral position. Both ratchet wheels are interconnected to the driving number wheel. One ratchet wheel is positioned for right-hand rotation and the other ratchet wheel for left-hand rotation. Hence, the driving number wheel is advanced by one ratchet wheel and retracted by the other ratchet Wheel. A positioner is incorporated which resiliently holds the driving number wheel and the other number wheels with their numbers properly centered in the sighting opening.

An embodiment of this invention is illustrated in the accompanying drawings in which:

Fig. 1 is a view in elevation of one side of a counter embodying the present invention;

Fig. 2 is a fragmentary view in elevation of the opposite side of such counter upon its being rotated about a horizontal axis;

Fig. 3 is an enlarged sectional view taken on the line 3 3 of Fig. 1;

Fig. 4 is a fragmentary sectional view taken on the line 4-4 of Fig. 1;

Fig. 5 is a fragmentary sectional view taken on the line 5-5 of Fig. l; and

Fig. 6 is a fragmentary view in elevation taken from the line 6--6 of Fig. 5.

In the drawings the add side of the counter is to the left and the subtract side to the right as viewed in Figs. 1 and 2. The embodiment of the add and subtract counter shown in the drawings is mounted in a casing 10 from the top of which depend a bracket 12 for mounting the shaft of the subtract assembly and a bracket 14 for mounting the shaft of the add assembly. The latter shaft also holds the transfer gears of the numeral wheels. A number wheel shaft 16, rotatively mounted in bearings initcd States atent ice 18 in the sides-of the casing 10, carries number wheels, driving wheel 20 'of which is pinned to such shaft. The driven number wheels 22 -are. freely rotatable with respect to such shaft. The driving number wheel 20 drives the adjacent wheel 22Tand it in turn drives the-succeeding wheel, etc., by means of wheelgears 24co-operab1e with transfer gears 26 of customary design. Thetransfer gears 26"a1'e carried on a shaft 28 extending between the bracket 14 and'the side. of the casing 10; These transfergears are pressed toward the add sideiof the casing by a compression spring 30 carried on such shaft. As wear takes place betweenzthe number wheels this spring will prevent slack and looseness from occurring between such wheels.

In the add operation ofthe counter the shaft 16 and the driving number wheel 20 are both driven in a counter? clockwise direction, as viewed in Fig. 3, by a ratchet wheel32 fixed to such'shaft; Also carried by such shaft either by being apart of such ratchet wheelor otherwise. secured thereto is holding disc '34'provided with peripheral notches wh ich are: resiliently engaged by a spring 36v to stop the driving number Wheel and the entire wheel assembly-with the numbers centrally fixed in a sight opening (not shown).

In the subtract function of the counter, the shaft 16 and the driving wheel 20 are both driven in an opposite direction of rotation (however, it is also counterclockwise as viewed in Fig. 4) by a ratchet wheel 38 also secured to the shaft 16. The faces of the teeth of the ratchet wheels are opposed and angularly aligned to provide equal angular motion in opposite directions.

The add ratchet wheel 32 is independently rotated by a drive-arm assembly 40 and the subtract ratchet wheel 38 is independently rotated by a drive-arm assembly 42. These assemblies are counterparts and their parts are identically numbered, only one assembly being described. These drive-arm assemblies are pivoted on opposite sides of the axis of shaft 16 with their faces toward each other and hence drive their related ratchet wheels in opposite rotation. Each drive-arm assembly includes a lever plate 44 provided with a bearing 46 by which it is mounted for oscillation on the supporting shaft (the lever plate). Since the lever plate extends on both sides of the shaft 16, it is provided with a slot 48 which is long enough to accommodate such shaft and provide for free movement of the lever plate relative thereto. The lever plate has pivotally mounted thereon a pawl with a ratchet engaging end 50 and a knockout end 52. This pawl is biased by a spring 54 so that the end 50 is continuously urged toward engagement with the teeth of the ratchet wheel. However, when the lever plate 44 is in its neutral position as shown in Fig. 3, the knockout end 52 will be engaged by a portion of the casing and hold the ratchet wheel engaging end 50 out of contact with such ratchet wheel. This permits one drive-arm assembly to operate the number wheels without interference from the drive-arm assembly in the neutral position. An anti-skip pin 56 of customary design is carried by the lever plate 44 and engages the face of a tooth on the ratchet wheel at the bottom of the driving stroke to prevent overthrow of the number wheels. Another anti-skip pin 58 is carried by the lever plate 44 so as to back up the end 50 of the pawl when the lever plate 44 has completed about half of its downward travel to hold such end within the outer peripheral confines of the teeth of the ratchet wheel and thus prevent such wheel from being spun past the tooth struck by the end 50 in the downward motion.

The add drive-arm assembly 40 is pivoted on the transfer gear shaft 28 and the subtract drive-arm assembly 42 is pivoted on a shaft 60 held between the bracket 12 and the side of the casing 10. Both of the lever plates are held in proper axial position along the shaft 16 by sleeves articles moving along one conveyor.

61 on such shaft having a diameter larger than the opening of the slot 48. Each drive-arm assembly is continuously urged into the neutral position shown in Fig. 3 by a coil spring 62, one end 64 of which is inserted in a hole 'in" the lever plate and the other end. 64 of which. fits in a slot in a bushing 68. This bushing is rotatively mounted in the casing 10 and may be rotated by split type screwdriver or the like to impress the proper tension on such spring.- When the desired tension is reached the bushing is locked by a set'screw 70 accessible from the side of casing 10. A

The add and subtract driveassemblies are separately rotated (from the neutral position shown in Fig. 3.to the end of the action stroke shown in Fig. 4 by a separate solenoid 72 connected by a link 74 to the leverplate 44. The height of each solenoid may. be adjusted relative to the casing to determine the length of the action stroke and adjust them for equalization and number-centering in a sight opening. The add solenoid may be attached to a sensing unit which is designed, for example, to count The subtract solenoid may be attached to another sensing unit which counts rejected articles transferred from such conveyor and placed on an adjacent conveyor. tract counter will show a total of accepted articles.

We claim:

1. An add and subtract counter having a frame, a num ber wheel shaft mounted in said frame, a series of coaxial rotary number wheels on said shaft, including a Thus the add and subdriving number wheel, means for transferring rotary motion from wheel-to wheel, a right hand and a left hand ratchet wheel secured to said shaft, means forming a driving connection between said ratchet wheels and said driving number wheel, oscillatory drive arm assemblies including lever plates pivotally mounted to said frame, said plates having slots through which said wheel shaft extends, pawls pivoted to said plates and movable therewith and operatively associated with said ratchet wheels for driving said ratchet wheels in oppositedirections, spring means urging said plates into engagement with said frame, said pawls having knockout ends engaged by said frame to disengage said pawls from said ratchet wheels to permit free movement of one ratchet wheel during the driving of the other, spring means carried by said plates to urge said pawls toward said ratchet wheels and means for selectively operating said drive arm assembly to cause said number wheels to add or subtract as the case may be.

2. An add and subtract counter as claimed in claim l in which said plates have abutment means limiting outward swinging of said pawls to preventsaid ratchet wheels from being spun past the tooth engaged by the ratchet.

References Cited in the file of this patent UNITED STATES PATENTS 

